001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.shiro.authz.annotation;
020
021import java.lang.annotation.Documented;
022import java.lang.annotation.ElementType;
023import java.lang.annotation.Retention;
024import java.lang.annotation.RetentionPolicy;
025import java.lang.annotation.Target;
026
027/**
028 * Requires the current Subject to be a &quot;guest&quot;, that is, they are not authenticated <em>or</em> remembered
029 * from a previous session for the annotated class/instance/method to be accessed or invoked.
030 * <p/>
031 * This annotation is the logical inverse of the {@link RequiresUser RequiresUser} annotation. That is,
032 * <code>RequiresUser == !RequiresGuest</code>, or more accurately,
033 * <p/>
034 * <code>RequiresGuest === subject.{@link org.apache.shiro.subject.Subject#getPrincipal() getPrincipal()} == null</code>.
035 *
036 * @see RequiresAuthentication
037 * @see RequiresUser
038 *
039 * @since 0.9.0
040 */
041@Target({ElementType.TYPE, ElementType.METHOD})
042@Retention(RetentionPolicy.RUNTIME)
043@Documented
044public @interface RequiresGuest {
045}